Stuart Pearce, the England Under-21s manager, has questioned why Arsène Wenger did not rest Jack Wilshere during the Premier League run-in if the Arsenal manager is so concerned about him suffering burnout.

Wilshere this week controversially withdrew from Pearce's squad for next month's European Under-21 Championships after becoming convinced he was risking injury by extending what has already been a 53-game season. It represented a dramatic U-turn from the midfielder, who had repeatedly declared his intention to play at the finals in Denmark.

It was also a major blow and an embarrassment for Pearce, who had been adamant when naming Wilshere in his 40-man provisional squad earlier this month that the 19-year-old would travel.

Wilshere changed his mind after being shown statistics by Arsenal's medical department which indicated he was becoming fatigued. But Pearce said on Thursday: "I would say that every player at this stage of the season would be reasonably tired. I'm talking about Spanish internationals, who we have to face, Czech internationals, who we have to face. Across the board at the end of a long season, players are more susceptible maybe to injury.

"One thing's for sure – Arsenal have not left him out of the side in the last six weeks of the season, even though the stats have said he's in the red zone."

Pearce otherwise refused to be drawn into a club-versus-country row, rejecting the suggestion Wilshere had been frightened into pulling out by his club. "I think Jack's got his own mind," said the former England left-back, who also insisted he had not been angered or hurt by the teenager's about-turn.

Pearce delayed naming his 23-man squad until after Sunday's final round of Premier League games, which led to Arsenal finishing fourth, forcing them to play a qualifying round to enter the Champions League group stage.

He played down the impact that Arsenal's earlier start to next season might have had on Wilshere's decision. "Arsène didn't want him to go full stop," Pearce said, adding that it would not upset him to see Wilshere play a full part in his club's summer tour of Asia. "What he does with Arsenal next season is irrelevant to me."

Andy Carroll was the other big-name absentee when Pearce announced his final 23 on Monday. The Liverpool striker was ruled out through injury but there have been question marks over his commitment to Under-21 football.

Pearce was reluctant to speak at length on Carroll, saying only: "I've not got a problem with any of the players with the Under-21s."

Pearce suffered a further blow on Thursday when another player with senior experience, Micah Richards, withdrew from the squad due to a hamstring problem. The Manchester City right-back reportedly had been earmarked as captain.

Pearce said: "We felt it was too much of a risk to wheel him out, with the possibility of it breaking down again. It wouldn't be fair on another player that would be fully fit."

He added: "He's a big member of the Under-21 party. "He played in the final, obviously, two years ago. He'll be a big miss for us. For me, at this stage, it's all about the 23 who are fit, available and ready to come and contribute."

Pearce said he had decided on Richards's replacement but would not announce it until the player himself had been informed. Despite the triple blow of being without Wilshere, Carroll and Richards, he refused to be downhearted about England's hopes in Denmark.

"The bulk of what we've done has probably been achieved with the likes of the squad as it stands at the moment," he said. "It won't be too much of a problem to us. We've got a fantastic spirit within the camp."